Presentation to NSMA conference
Rosslyn, VA
May 21, 2002
Software Radio Technology
Dr. John Chapin
CTO
Vanu, Inc.
One Porter Square, Suite 18
Cambridge, MA 02474
http://www.vanu.com
1
Vanu, Inc.
• Overview
– Founded September 1998
– Spin-off from MIT SDR research project 1994–1998
– Software vendor
• Contracts
–
–
–
–
–
May 2002
Military
Public Safety
Basic Research
Automotive
Surveillance
DARPA, JTRS Joint Program Office
National Institute of Justice
National Science Foundation, MDA
Telematics device for a Tier 1 Supplier
Major defense conglomerate
© 2002
2
Software Radio
• Hardware Radio
– Separate devices for different functions
– Any fix or upgrade needs a hardware change
PCS voice
Analog VHF
APCO P25
WLAN
• Software Radio
– One device for many functions
– Upgrade through software change
May 2002
© 2002
3
SDR status in USA
• Military
– Harris Falcon II, Motorola WITS
– Since 1999, all DOD tactical radio procurements must be SDR
– Military SDR standard: Joint Tactical Radio System (JTRS)
• Civilian
– SDR devices always certifiable as if they were legacy devices
– FCC task force began in 1998 on SDR-specific rules
– Docket 00-47
• Notice of Inquiry
March 2000
• NPRM
December 2000
• First R&O
September 2001
May 2002
© 2002
4
Different types of software radios
• Portable SDR (a.k.a. Pure SWR)
– Software costs amortized over many platforms
– Easily upgrade hardware over time
• Reconfigurable SDR
– All signal processing reconfigurable
– Significant use of FPGA or assembly code
• Modal SDR
– Software controls and configures the radio
– ASIC or analog hardware
May 2002
© 2002
Vanu
RadioScape
SpeakEasy
AirNet
Dual-mode
cell phone
5
SDR internals
voice
data
baseband
IF
Embedded computer
All waveform-specific
functions in software
May 2002
Radio Front End
antenna
RF tuning
Analog-Digital Conversion
Channelization
No waveform-specific processing
© 2002
6
Software Radio Phase Space
A:
B:
C:
D:
V:
X:
HF STR-2000
COTS Handset
SWR Cell Site
SPEAKeasy II
Vanu, Inc. Software Radio
Ideal Software Radio
Source: Mitola, Joseph. “Software Radio Architecture: A Mathematical Perspective”, IEEE JSAC, April 1999.
May 2002
© 2002
7
Vanu status: Radio Front End for Agility
– Ideal future platform, cost $10s
– Manufacturers waiting for market to develop
• Multiple-IC board
– Prototype quantities this summer
– 30-512 MHZ, worldwide cellular & PCS bands
– Low power, full duplex, cost $100s
• Discrete components
– Current TX limited to < 1 GHz, < 1 MHz wide
– Separate front ends for receive and transmit
– Cost $1000s
May 2002
© 2002
TECHNOLOGY PROGRESS
• Single IC
8
Vanu status: Processing for Flexibility
35
29
% of CPU
30
25
22
Pentium III
800-1000 MHz
StrongARM
200 MHz
20
15
9.6
10
5
2.7
0
IS-136
30kHz
May 2002
GSM
200kHz
FamBand
25kHz
© 2002
9
SDR tradeoffs
• Higher power consumption
– Reconfigurable processing vs dedicated circuits
– Primarily an issue for battery-powered devices
• Sensitivity/selectivity of radio front end
– Challenging to achieve if highly agile system
– Primarily an issue for surveillance, military applications
• Lower gain if antenna is multi-band
– Easy solution: attach 2 or 3 antennas
– Primarily an issue for handheld devices
• SDR ready today for many uses
May 2002
© 2002
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For more information
• http://www.sdrforum.org
• FCC Docket 00-47
• Two new books from Wiley
– Tuttlebee, W., editor
– Chapters by all the major players in the field
– Software Defined Radio: Origins, Drivers and International
Perspectives
– Software Defined Radio: Enabling Technology
• http://www.vanu.com
– John Chapin
[email protected]
May 2002
© 2002
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